Question

Q2.3. What is the lowest value for proportion to vaccinate that protects the entire population from a smallpox epidemic

Answer 1

0.85 ( lowest value proportion to vaccinate )

Explanation:

Using the herd immunity relationship

Vc = E - ( E / Ro )

Vc = critical vaccination level

E = vaccine effective against the transmission = 1

Ro = Basic reproduction number

lets assume the effectiveness of the transmission = 100% = 1

lets assume the

Vc = 1 - ( 1 / 3 ) = 67%

but the lowest value proportion to vaccinate = 85%